Grey Systems: Theory and Application, an international journal founded by Professor Liu Sifeng of Nanjing University of Aeronautics and Astronautics (NUAA), has been included in the 2025 list of world-class academic journals published by the Institute of Scientific and Technical Information of China (ISTIC) and partner institutions. The news came as NUAA hosted GSUA 2026, an international grey systems conference, in October 2026.
Grey systems theory studies how to make reliable decisions and forecasts when data are scarce or incomplete — "small-sample, poor-information" problems that are common in economics, engineering, supply chains and management. NUAA's Institute for Grey Systems Studies, founded by Professor Liu, specialises in these problems.
Key facts
Journal: Grey Systems: Theory and Application, launched in 2011 and published quarterly by Emerald Publishing (UK).
Founder and editor-in-chief: Professor Liu Sifeng, founding director of NUAA's Institute for Grey Systems Studies.
Output: 16 volumes and about 610 papers.
Ranking: 10th of 137 journals in the Journal Citation Reports category "Mathematics, Interdisciplinary Applications".
Recognition: included in the 2025 list of world-class academic journals issued by ISTIC and partner institutions.
Conference: GSUA 2026, 16–18 October 2026 in Nanjing, with around 300 scholars.
About the journal
Professor Liu proposed the journal to Emerald Publishing in 2010, and it published its first issue in 2011. According to NUAA's College of Economics and Management, it has been indexed in the Science Citation Index since 2019, has been in the top quartile (Q1) of the Journal Citation Reports since 2022, and is also indexed in EI Compendex and Scopus.
GSUA 2026 brings the field to Nanjing
NUAA hosted the 2026 International Conference on Grey Systems and Uncertainty Analysis (GSUA 2026) on 16–18 October. Scholars came from institutions including Imperial College London, De Montfort University, the University of Valladolid, KEDGE Business School, Poznan University of Technology, the Bucharest University of Economic Studies, Süleyman Demirel University and Sabaragamuwa University of Sri Lanka, as well as from Cameroon and leading Chinese universities. The programme included 7 keynote talks — on topics such as explainable grey AI and supply-chain forecasting — and 10 parallel sessions. A new Grey Systems Theory AI knowledge base, built by the NUAA Library, the College of Economics and Management and the Institute for Grey Systems Studies, was also launched.
What this means for international students
Students interested in management science, forecasting, data analysis or decision-making under uncertainty can study with the research group behind the field's international journal and conference. Explore NUAA's master's and PhD programmes or find a supervisor in the College of Economics and Management.
Frequently asked questions
What is grey systems theory?
Grey systems theory is a method for analysing and forecasting systems when only small or incomplete data samples are available. It is used in economics, engineering, supply chains and management, and NUAA's Professor Liu Sifeng is President of the international GSUA federation.
Who publishes Grey Systems: Theory and Application?
The journal is published quarterly by Emerald Publishing in the UK. It was founded in 2011 on the initiative of NUAA's Professor Liu Sifeng, who is its editor-in-chief, and has published about 610 papers.
Can international students study grey systems at NUAA?
Yes. NUAA's Institute for Grey Systems Studies and College of Economics and Management supervise master's and PhD research, and international applicants can choose a supervisor working on grey systems, forecasting or uncertainty analysis.
Sources: NUAA English News · NUAA College of Economics and Management · NUAA News (GSUA 2026)
